The field of the present invention is compositions based on high ortho alkoxymethyl and aralkoxymethyl etherified phenolformaldehyde resins.
Phenolic ethers have been described in Kirk-Othmer "Encyclopedia of Chemical Technology", 2nd Edition, Vol. 8 (1965), pages 165-175 in which the phenolic aromatic hydroxyl is etherified as an aryl ether. In the case of the resole ethers which are characterized by having the methylol group ortho and para to the free aromatic hydroxyl etherified, relatively little prior art is known. The state of known prior art is set forth in U.S. Pat. No. 2,454,153, U.S. Pat. No. 3,630,977 and U.S. Pat. No. 3,650,996 which disclose the utility of ethers derived from methylol derivatives of difunctional phenols. The ethers described have the disadvantage of having only two reactive sites and, hence, are not self-curable and their chemical and solvent resistance is impaired. In U.S. Pat. No. 3,485,797 there are disclosed resole resin containing internal benzylic ether linkages only as contrasted to the present invention having both internal benzylic ether and alkoxymethyl or aralkoxymethyl ether linkages.
It is the objective of the present invention then to provide novel resole resins characterized by having either aralkoxymethyl and alkoxymethyl ether groups incorporated in their resole structure. The resoles are also characterized by having ortho-ortho and ortho-para functionality capable of being cured at elevated temperatures yet having great storage stability at temperatures of about 20.degree.-25.degree. C.
Another objective is to provide said resole resins that have high compatibility and reactivity with co-reacting resins such as alkyds, epoxies, polyvinyl formals and butryals.
Finally, it is an objective to provide methods of preparing said novel etherified resole resins.